1. Field of the Invention
This invention relates to catalytic reaction apparatus such as for producing product gases from a feedstock.
2. Description of the Prior Art
Catalytic reaction apparatus for converting hydrocarbon feedstocks (fuels) to useful industrial gases, such as hydrogen, are well known in the art. The most common process for producing hydrogen is steam reforming a hydrocarbon fuel by passing it through catalyst filled reaction tubes disposed within a furnace. In commercial size plants radiation from the furnace walls is the primary mode of heat transfer to the reaction tubes. This requires relatively large spacing between the tubes and having all of the tubes adjacent the walls of the furnace in order that each tube is uniformly heated by radiation from the walls. It is, therefore, not possible to dispose a large number of reaction tubes compactly within the furnace since the tubes adjacent the walls will become much hotter than those which are surrounded by other tubes; also, portions of individual tubes which do not have a direct line of sight with the furnace wall will be cooler than those portions of the same tube which do have a direct line of sight to the furnace wall, thereby resulting in nonuniform circumferential distribution of heat within certain reaction tubes. This results in reduced life of the apparatus due to local hot spots and prevents the most efficient use of the heat energy within the furnace.